The present invention relates to a method and apparatus for testing containers and, more particularly, relates to a method and apparatus for individually testing containers for structural strength and for flaws which might cause ruptures or leaks when the containers are sealed with pressurized contents.
In-line machine testing of containers such as bottles or cans to pressures up to about 230 pounds per square inch gauge (psig) to test structural flaws in the container is well known. Containers are fed sequentially to a testing machine and high pressure air introduced into the containers for a predetermined period of time after which the air is exhausted to the atmosphere. This procedure is not only energy inefficient because of the high volumes of pressurized air required but also creates a hazardous work environment because of the loud ear-damaging sounds emitted by the escaping air.
U.S. Pat. No. 3,751,973 issued Aug. 14, 1973 discloses a bottle testing method and apparatus for pressure testing bottles and for possible flaws in which bottles are fed through an opening in a stationary shield to a rotating turret having peripheral cells. Each cell is sealed while pressurized air is forced into the bottles and, prior to exhausting air from tested bottles, coupling means are provided to communicate the tested bottles directly with bottles entering the testing sequence to reduce compressed air requirements. This apparatus requires a fairly complex conduit system for interconnecting discharging bottles with incoming bottles.